LED YELLOW DIFFUSED T-1 3/4 T/H 4304S7 Equivalent & Substitute Parts

Part Overview

The 4304S7 is a yellow diffused LED in T-1 3/4 (5mm) through-hole package manufactured by Visual Communications Company (VCC). This component is classified as obsolete, indicating discontinued production and limited availability. The part functions as a yellow LED indication element with a 2V forward voltage and 4mcd brightness rating, designed for discrete radial mounting applications.

Due to obsolete status, equivalent substitute parts from active manufacturers are necessary for new designs, production continuity, and long-term component sourcing. The substitute parts listed maintain compatibility within the yellow LED T-1 3/4 through-hole category while meeting current RoHS3 compliance requirements.

Substiute Parts

4304S7

Visual Communications Company - VCCIn Stock: 10274304S7 Datasheet

Current PartRFQ

HLMP-3451

Broadcom LimitedIn Stock: 20873HLMP-3451 Datasheet

SimilarRFQ

WP63YD

KingbrightIn Stock: 1116WP63YD Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution logic for the 4304S7 is based on the following allowed parameters:

Primary Compatibility Criteria:

• Lens Color: Yellow (all substitutes match)
• Lens Transparency: Diffused (all substitutes match)
• Lens Size: T-1 3/4 (5mm) (all substitutes match)
• Mounting Type: Through Hole Radial (all substitutes match)
• Package / Case: Radial (all substitutes match)
• RoHS Status: ROHS3 Compliant (all substitutes match)

Secondary Compatibility Parameters (Allowable Variation):

• Voltage - Forward (Vf): 2V to 2.1V range (acceptable for most circuit designs with resistor adjustment)
• Current - Test: 10mA to 20mA (operational range for yellow LEDs in this package)
• Millicandela Rating: 3.6mcd to 10mcd (brightness variation acceptable depending on application requirements)
• Viewing Angle: 50° to 60° (both provide adequate visibility for indication applications)
• Wavelength - Peak: 583nm to 590nm (all within yellow spectrum range)

Identified Substitute Parts:

1. HLMP-3451 (Broadcom Limited) - Active status, 3.6mcd, 2V, 50° viewing angle
2. WP63YD (Kingbright) - Active status, 10mcd, 2.1V, 60° viewing angle

Both substitutes maintain mechanical and electrical compatibility within the specified parameter ranges while offering active product status and current manufacturing availability.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Minimum Design Changes):

HLMP-3451 (Broadcom Limited) is the closest functional equivalent to the 4304S7. This substitute maintains identical forward voltage (2V), test current (10mA), and viewing angle (50°). The millicandela rating of 3.6mcd is marginally lower than the original 4mcd specification, representing a 10% reduction in brightness. This part carries active product status with established manufacturing continuity and ROHS3 compliance certification. Height specification of 6.35mm represents a 1.02mm increase over the original 5.33mm, which remains within acceptable through-hole PCB design tolerances.

For Applications Requiring Higher Brightness:

WP63YD (Kingbright) provides 10mcd brightness output, representing a 150% increase over the original 4304S7 specification. This substitute operates at 2.1V forward voltage (0.1V higher) and 20mA test current (double the original specification). Circuit design modifications are required: series resistor recalculation for the increased forward voltage and current draw. The 60° viewing angle provides 10° additional angular coverage compared to the original 50° specification. This part is suitable for applications where enhanced visibility is required or where the original brightness was marginal for the intended environment. Active product status and ROHS3 compliance are confirmed.

Compliance and Availability Considerations:

Both substitute parts maintain ROHS3 compliance, MSL rating of 1 (Unlimited), and EAR99 export classification, matching the regulatory profile of the obsolete 4304S7. Broadcom HLMP-3451 demonstrates higher inventory availability (20,818 pcs) compared to Kingbright WP63YD (1,097 pcs), supporting long-term production planning and supply chain stability.

Frequently Asked Questions (FAQ)

Q: Can HLMP-3451 be used as a direct drop-in replacement for 4304S7 without circuit modifications?

A: Yes. HLMP-3451 maintains identical forward voltage (2V) and test current (10mA) specifications. The 0.4mcd brightness reduction (3.6mcd vs. 4mcd) and 1.02mm height increase are within acceptable engineering tolerances for most indication applications. No resistor or power supply adjustments are required.

Q: What circuit changes are necessary if WP63YD is selected instead of 4304S7?

A: WP63YD operates at 2.1V forward voltage and 20mA test current, compared to 2V and 10mA for the original part. The series current-limiting resistor must be recalculated using Ohm's law: R = (Vsupply - Vf) / I. For example, on a 5V supply: original design uses (5V - 2V) / 10mA = 300Ω; WP63YD requires (5V - 2.1V) / 20mA = 145Ω. Power supply current capacity must also be verified to accommodate doubled current draw per LED.

Q: Are there mechanical compatibility issues between these substitutes and the original 4304S7?

A: All three parts use identical T-1 3/4 (5mm) through-hole radial packages with standard PCB footprints. Height variations (5.33mm original, 6.35mm HLMP-3451, 6.00mm WP63YD) are within typical through-hole design clearances. No PCB layout modifications are required.

Q: Which substitute part should be selected for new product designs?

A: HLMP-3451 is recommended for new designs requiring direct electrical compatibility with existing circuits. WP63YD is appropriate when enhanced brightness is a design requirement or when the original 4mcd specification was marginal for the application environment. Both parts carry active product status, ensuring long-term availability and manufacturing support.

Q: Do these substitute parts meet the same regulatory requirements as the original 4304S7?

A: Yes. Both HLMP-3451 and WP63YD are ROHS3 compliant with MSL rating 1 (Unlimited) and EAR99 export classification, matching the regulatory profile of the obsolete 4304S7. No additional compliance documentation or certification is required for equivalent substitution.

Q: What is the wavelength difference between these parts, and does it affect visual appearance?

A: Peak wavelengths are 583nm (4304S7 and HLMP-3451) and 590nm (WP63YD). All three wavelengths fall within the yellow spectrum range (570nm to 590nm). The 7nm difference between HLMP-3451 and WP63YD is imperceptible to human vision; both will appear as standard yellow indication LEDs in practical applications.

Q: Are there inventory or lead-time considerations for these substitutes?

A: HLMP-3451 demonstrates significantly higher inventory availability (20,818 pcs) compared to WP63YD (1,097 pcs). For production quantities or long-term supply planning, HLMP-3451 offers superior supply chain stability and shorter lead times.